Answer:
I needed to use good precision in my measurement for my chemistry lab
Explanation:
D. microwaves, Ultraviolet, x-rays
Fe2O3 because O has a -2 charge and Fe and +3, you want the charges to equal each other so if you have 2 Fe with +3 charge the charge becomes 6 if you have 3 O with -2 charge the charge becomes 6.
Explanation:
2H2 + O2 = 2H2O
2mol. 1mol. 2mol
2mol reacts with 1mol
13mol reacts with x
x=<u>13mol</u><u> </u><u>×</u><u> </u><u>1mol</u>
<u> </u><u> </u><u> </u><u> </u><u> </u><u> </u><u> </u><u> </u><u> </u><u>2mol</u>
x= <u>13mol</u>
<u> </u><u> </u><u> </u><u> </u><u> </u><u> </u>2mol
x= 6.5mol of oxygen
The combustion of naphthalene is given as:
C10H8 (s) + 12 O2 (g) --> 10CO2 (g) + 4 H2O (l)
Enthalpy of combustion ΔH = -5157 kJ/mol
Now, the enthalpy change of a reaction is given
ΔH = ∑nΔHf (products) - ∑nΔHf (reactants)
where n = number of moles
ΔHf = enthalpy of formation
Therefore,
ΔH = [10*ΔHf(CO2) + 4*ΔHf(H2O)] - [1*ΔHf(C10H8) + 12*O2]
-5157 = [10*(-393.5) + 4*(285.83)] - [ΔHf(C10H8) + 12*(0)]
ΔHf(C10H8) = 78.68 kJ/mol
